The purpose of this study is to obtain baseline data on aging in well women with reference to hormone profiles, life-health histories, psychosocial adaptation and physical health. Aging is defined by chronological age (spanning four decades of life) and biologic age (in terms of menstrual and hormonal status). A sample of 120 women between the ages of 36-45, 46-55, 56-65 and 66-75 will be selected in cells of 30 each. An additional 60 women, equally divided between age categories 36-45 and 46-55 will be selected on the basis of their menstrual status for the study of biological aging. All subjects will be: (1) in normal health; (2) white; (3) parous and have at least 10 years of education. Each subject will have an evaluation of their life-health history, psychological assessment, medical and gynecological exam and a full hormonal profile of the sex steroids (Gonadotropin releasing hormone, luteinizing hormone, follicle stimulating hormone, estrone, Estradiol, Androstenedione, Dihydrotestosterone, Testosterone and Progesterone) and the brain catecholamine metabolite, MHPG. In addition, a physical fitness assessment and a measure of the trace element zinc, folacin and iron will be made as an index of the subject's state of nutritional well-being. This research will provide baseline information needed before comparative research, e.g., in black women, can be undertaken.